Method of analyzing a disposable test swipe

ABSTRACT

A portable chemical analytical apparatus to analyze a test swipe includes a heater to warm the test swipe to a predetermined temperature; a clamp to secure the test swipe to the heater; one or more pumps to dispense one or more chemicals onto the test swipe from a disposable cartridge; a fan to remove chemical vapors rising a predetermined distance from the test swipe; and a camera to capture an image of the test swipe for automated analysis.

This application is a continuation of U.S. application Ser. No.12/354,960 filed Jan. 16, 2009 now U.S. Pat. No. 8,071,385, the contentof which is incorporated by reference.

BACKGROUND

This invention relates to systems for the detection of explosives andother controlled substances such as drugs or narcotics as well as otherchemicals used in clandestine activities.

Recent terror attacks have changed the dynamics of the explosivedetection systems across the globe. Terrorists, acting singly or inconcert, instill immense fear and apprehension in civilians andgovernments alike with their technical knowledge about explosives. Inparallel, the world has experienced an increase in the transportation ofcontraband substances such as drugs or narcotics.

With advances in explosives technology, such as the advent of theplastic explosives, which can be disguised as common items, it isbecoming increasingly difficult to detect these substances. The problemsthat must be overcome in the detection of these substances as well asothers, include low vapor pressure of the particular vapors escapingfrom the particular substance, the search time and the throughput of thevarious systems, the low concentration of vapor or particulate emissionsfrom the particular substance, isolation of the particular substancewith a high degree of reliability, and maintaining the integrity of thesystems environment.

Various techniques for detecting substances such as explosives and drugsor narcotics have been developed, ranging from explosives/drug sniffingdogs to highly sophisticated vapor detection devices. Machine detectionof the aforementioned substances can be accomplished through non-vapordetection or vapor detection. Non-vapor detection methods include x-raydetection, gamma-ray detection, neutron activation detection and nuclearmagnetic resonance detection. These methods of detection are moreapplicable to the detection of the various substances when thesubstances are concealed and are carried or associated with non-livingitems such as baggage as these techniques might pose a threat to livingitems. Vapor detection methods include electron capture detection, gaschromatography detection, mass spectroscopy detection, plasmachromatography detection, bio-sensor detection and laser photo-acousticdetection. These methods of detection are more applicable to thedetection of substances that are concealed and associated with livingspecimens.

Conventional systems tend to be large and immobile. Further, currentsystems can require users to manually apply toxic chemicals as testingagents. As a result, conventional systems are not mobile and hard touse. Hence, their adoption for field use has been limited.

SUMMARY

In one aspect, a portable handheld chemical analytical apparatus toanalyze a test swipe for chemicals such as household, drug, andclandestine, and explosive chemicals is disclosed. The apparatusincludes a heater to warm the test swipe to a predetermined temperature;a clamp to secure the test swipe to the heater; one or more pumps todispense one or more chemicals onto the test swipe; a fan to circulatechemical vapors rising from the test swipe; and a camera to capture animage of the test swipe for analysis.

In another aspect, a method to analyze a swiped sample to identify achemical composition, includes automatically pumping a series ofchemical solution agents into the swiped sample; heating the swipedsample to one or more predetermined temperatures to accelerate thechemical reactions; capturing one or more images of the chemicalreaction; sending the images to the a display screen for operatorobservation; and analyzing the images to identify the chemicalcomposition based on a chemical reaction database.

Advantages of the system may include one or more of the following. Thesystem tests the presence of chemical materials or compounds using anumber of factors or parameters singly or in concert. The factors caninclude heat, volume, time, temperature, and vapor control, among othersand sequences these factors over time. The sequences can be in uniqueintervals. As a result, the system is highly reliable and reduces “falsepositives” due to its multi-factor, multi-step diagnostic operations.

The system significantly enhances the possibility of accurately andquickly screening personnel, equipment, and materials at securitycheckpoints, military operations, law enforcement, or other screeningscenarios, and for detecting trace of explosive materials. The systemallows users to precisely and quickly detect different explosivechemical agents.

The system operates in a real-time fashion. It automatically dispenses aprecise volume of chemical solutions over time when requested. Thesystem optionally allows users to manually control the sequence of thepumping process. The system provides users with pump controls fordispensing chemical solutions. Through the built-in heater, the systemautomatically heats up the swiped sample to predetermined temperaturesover specific time parameters using an automatic ramped heating feedbackcontrol. The system automatically and continually performs self-checkand monitors fluid levels, temperature and time. The systemautomatically chronologically stores data and arranges according topositive results versus negative results. The system automatically tellsthe operator to remove the analyzed swipe. The system delivers a uniquesequence of precise chemical volumes under time, heat, and vaporparameters. The system has detachable and expendable chemical(s) incartridge form for ease of replacement. The system uses ahigh-resolution digital camera for data collection and analysis.

By use of a wired or wireless transceiver, detected information can beeasily transmitted to anywhere in the world. By replacing disposableswipes/pads/swabs and disposable chemical test reservoirs, the systemcan detect a wide range of explosives, clandestine material, drugs, andhousehold products used to manufacture explosives, a range of controlledchemical agents, drugs, and narcotics etc. By allowing the user to swaptest materials and running a computerized diagnostics, the user caneasily and effectively change the system to meet what is considered tobe the threat at that time. By having all components under programcontrol and by arranging for a known input to the system such as acontrolled injection of target material, the system can performself-calibration and self-diagnostic.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features, and advantages of the presentinvention will be better understood from the following detaileddescriptions taken in conjunction with the accompanying drawings, all ofwhich are given by way of illustration only, and are not imitative ofthe present invention, in which:

FIG. 1 shows an exemplary portable chemical detection device.

FIGS. 2A and 2B show in more details major components of the device.

FIG. 3 shows in more details a swipe receiving port.

FIG. 4A shows a perspective view of a chemical supply cartridge.

FIG. 4B shows an exemplary perspective top view of a pump assembly.

FIG. 4C shows an exemplary perspective view of a micro-pump array.

FIG. 5A shows an exemplary perspective view of a camera in a testchamber.

FIG. 5B shows an exemplary perspective view of tubing and cameraactuator in the test chamber.

FIG. 6 shows an exemplary block diagram of processing electronics forthe system of FIG. 1.

FIGS. 7A-7D show an exemplary operational flow chart executed by thesystem of FIG. 1.

FIG. 8 shows an exemplary image analysis process executed by theprocessor of FIG. 5 to detect chemical agents automatically.

DESCRIPTION

The following detailed description of the invention is provided to aidthose skilled in the art in practicing the present invention. Even so,the following detailed description of the invention should not beconstrued to unduly limit the present invention, as modifications andvariations in the embodiments herein discussed may be made by those ofordinary skill in the art without departing from the spirit or scope ofthe present inventive discovery.

FIG. 1 shows an exemplary portable chemical detection device 10. Thedevice 10 has a housing 20 that supports a display 22 and input devicessuch as an on-off button 24 and navigation/selection buttons 26. In oneembodiment, the system has six buttons. The first button is the On/Offbutton. This button allows user to turn the unit on or off. Theremaining five buttons (Left, Right, Down, Up, and Enter) allows user tointeract with a Graphical User Interface (GUI) of the system. The GUI isflexible, efficient and user friendly.

The device 10 also has an input/output port 28 such as a USB port orFirewire port to communicate with a remote computer, and AC power port,among others. In one embodiment, the I/O port 28 is a weather proof PCinterface. The PC interface can set up operation parameters and recoveranalyzed data. In another embodiment, the I/O port 28 can include aflash memory card interface.

The device 10 also includes two ports 30 and 40 to receive userreplaceable media and chemical. The device 10 also includes a port 41Ato receive user replaceable DC battery cartridge. Port 30 receives atest swipe 32. The port 40 receives a chemical cartridge, which canhouse one or more chemical containers. An electronic controller 58(shown in FIGS. 2A AND 2B) receives inputs from the buttons or keys andcontrols the display 22 and other electronics in the device 10. Thesystem can work with different power sources including battery port 41Aport and/or a DC input port 41B such as a car jack or an AC/DC adaptor.

The system of FIG. 1 is preferably a hand-held unit, which can mostpreferably be operated easily in real time by one operator. Moreover,the operation of such detectors should preferably be simple so thatnon-technical persons can operate the instrument properly, efficiently,and easily.

FIGS. 2A and 2B are two perspective top views that show in more detailsmajor components of the device 10. In the embodiment of FIG. 2A, aplurality of chemical containers or reservoirs 42 are mounted in adisposable cartridge 44 that is inserted into the unit 10. Thereservoirs 42 are punctured via safety needles with a side port and thechemicals are automatically or manually pumped from the reservoirs 42 byone or more micro-pumps 46. The chemicals are delivered through one ormore short length and narrow ID delivery tubes connected to the outputsof the micro-pumps 46 to the test swipe 32 during testing.

To test a contaminate collection swipe, a user opens the port 30 andplaces a test swipe 32 into a swipe holder 34. The swipe holder 34 movesalong sliding rails 36 when the user closes the port 30 to place thetest swipe 32 under a test chamber 38. The test chamber 38 includes achamber with two openings 52 that face a variable speed fan 54 to drawair across the test swab 32 while under test. The test chamber alsoincludes a heating element 56 connected to a PID loop that can warm upthe test swab 32 to multiple predetermined temperature settings duringtest. The test chamber also contains a camera 39 (FIGS. 2A, 2B, and 5A)

FIG. 3 shows in more detail port 30 that receives the test swipe 32 inthe swipe holder 44 34. The swipe holder 34 includes a door 60 by whicha user can press against to open or close the port 30. The swipe holder34 also includes an open face press-fit clamp 62 that secures the swipe32 against a heating element 64 under the swipe 32 upon closure. Theswipe holder 34 is attached to rails 66 that slide within rails 68 toenable the swipe holder 34 carrying the test swab 32 to move in and outof the device 10. An enclosure for the swipe holder 34 is formed bypositioning a lid 70 with an opening 72 between the sliding rails 68.The opening 72 allows movable tubes from the micro-pumps 46 to dispensetest chemicals onto the 32. The opening 72 also allows a camera 39 (FIG.5A) to capture images of the test results for automatic real-timeanalysis of the test. A white-light source such as an LED is positionednear the camera can be turned on to provide lighting if needed andturned off when not used to conserve power. In one embodiment, thecamera output is shown on the display 22 so that the user or operatorcan visually determine the test result(s) while the automateddetermination is in progress. The opening 72 also allows a variablespeed fan 54 to gently move vapor away from the camera lens to avoidfogging the lens (anti-fogging).

FIG. 4A shows a perspective view of a disposable chemical supplycartridge 44 that can be inserted into the port 40. The disposablecartridge 44 contains one or more reservoirs 80, each having an inlet 82that can be punctured and is re-sealable so that the chemical in eachreservoir 80 can be accessed by a tip or safety needle 84. Thedisposable cartridge 44 also has a key 86 cooperating with a recess 87(FIG. 4B) to ensure that the cartridge 44 can only be inserted in apredetermined orientation.

FIG. 4B shows a pump assembly with the cartridge 44. The needles 84provide chemicals through short length, narrow gauge tubes (not shown)to their respective inputs 90 at the micro-pumps 46.

FIG. 4C shows an exemplary perspective view of a micro-pump array. Asshown therein, a plurality of micro-pumps 46 are provided to pump aseries of respective chemicals from the array of reservoirs 80. Eachmicro-pump has an inlet 90 that is connected to the needles that may ormay not include safety tips and that are inserted into each reservoir 80when the user inserts the cartridge 44 into the device 10. Another setof tubes are connected to the outputs of the micro-pumps 46 to deliverthe chemicals in precise volume, sequence and timing as controlled bythe processing electronic controller 58.

FIGS. 5A and 5B show an exemplary perspective view of a camera 39 inconjunction with the test chamber 38. The chamber 38 includes a motor 92driving a gear 94. The gear 94 cooperates with a moveable arm 96 thatmoves test tubing fixture 98 back and forth over the test swab 32 duringtesting. The test tubing fixture 96 moves very closely to the swipe 32for chemical deposit onto the swipe when the device 10 is held in anyorientation. The arm 96 includes a plurality of openings that receive aplurality of tubes from the output of the micropumps 46. The arm 96 alsomoves the fixture 98 out of the way for the camera 39 to capture changeson the test swipe 32 during testing. The camera images are thenanalyzed, and the result can then be displayed on the display 22. In oneembodiment, the camera 39 can capture raw images with 65,536 colors. Thecamera is protected with an anti-fog feature using the adjustable speedfan 54. The image data can be shown continuously throughout the entireprocess on a flip-up display 22 with high fidelity. In one embodiment,the system provides a software JPEG encoder and decoder for storing andviewing previous results and images. The system also includes whitelight LEDs (not shown) located within the test chamber 38 that provideseven, shadow free, and uniform lighting during camera 39's operationwith a programmable white light intensity. The LEDs minimize shadows inthe camera viewing area.

The swipe holder 34 moves along rugged sliding rails 66 when the usercloses the port 30 to place the test swipe 32 under the test chamber 38.The test chamber 38 includes a chamber with two openings 52 that facethe fan 54 to draw air across the test swipe 32 while under test. Thetest chamber also includes a heating element 56 that can warm up thetest swipe 32 to a predetermined temperature during test.

FIG. 6 shows an exemplary block diagram of processing electronics forthe system of FIG. 1. A processor 200 controls all tasks done by thesystem. The processor 200 communicates over a bus 202 to variousdevices, including buttons interface 204, fan driver 206, speaker driver208, display controller 210, micro-pump driver 212, and USB controller214. The processor 200 also communicates with embedded memory 220 and aprogrammable ROM 224 that contains boot code as well as applicationcode. The processor 200 also drives buffers 226, 228 and 230 whichcontrols the LED, infrared sensor that informs the operator if a swipehas been loaded into the test chamber 38, and heat filament,respectively. The infrared sensor is positioned under the swipe and actsas a proximity sensor to detect the presence or absence of a swipe bythe amount of light reflected back. The processor 200 or controlleractuates the motor to drive a solution delivery manifold to the centerof the swipe and in close proximity to the swipe to dispense thesolution without dripping, regardless orientation. The controller canmonitor fluid levels within each reservoir contained in the disposablecartridge. This is done by decrementing available volume each time thepump is actuated and when the count reaches a low threshold, thecontroller can indicate that the reservoir is out of chemical.

The system is powered by a 12-volt DC source, which can be generatedfrom an AC/DC converter, a car outlet or from eight 1.5-volt batteriesin series. The highest prioritized energy source is from an AC/DCconverter followed by the one from a car outlet, then the energy frombatteries. The 12-volt DC power source will supply current to the heaterand the pump. It is also connected to the low drop voltage regulator togenerate different voltage levels such as 5 V, 2.8 V and 3.3 V, whichare necessary for the processor and for other peripherals as well.

In one embodiment as a Portable Explosive Trace Detector (PETD), thesystem of FIG. 6 significantly enhances the detection of the explosivematerials as well as speeding up the screening and detecting proceduresat security checkpoints. First, the PETD automatically pumps a series ofchemical solution agents into the swiped sample and heats up to specifictemperature to accelerate the chemical reactions. Second, an internalCMOS camera captures the chemical reaction images at its highestresolution, raw data for better image analysis. Third it then sendsthese raw images data to the LCD (Liquid Crystal Display) screen for thepurpose of observation. Moreover, the JPEG codec will be develop forstoring and replaying image functions. The LCD screen provides a highquality image for human viewing. The LCD can analyze the image toidentify explosive materials based on the provided chemical reactiondatabase. Last but not least, the PC interfaces can be used to updatesoftware and firmware as well as to backup the data.

In one implementation, to start the analysis process, the system turnsthe micro-pump(s) N (i.e., N=1, 2, 3 . . . or a combination thereof) todisperse the chemical solution into the Swiped Sample. The pumping rateis set to 2 Hz. After dispersing chemical solution, the system startsheating the sample to excite the chemical reactions under controlledvapor, time, temperature, and chemical volume conditions specific to aparticular analyte or group of analytes. A current of about one ampereis applied to heat up the heating filament. During the heating process,the fluctuation of the temperature is controlled by a feedback circuitwith a thermistor.

When the temperature of the sample swipe reaches a predefined value, thesystem turns the heater off, the white light LED on and the fan on. Thespeed of the fan is adjustable using pulse width modulation control inone embodiment.

Before commanding the camera's CMOS image sensor to capture an image,the system waits for the chemical reaction to complete for around 1 ms.The captured image is then displayed on the LCD.

The system creates a result image by subtracting the captured image fromthe background one. Then the result image is compared with the colorpatterns in the lookup table stored in the system. If the results imagematches some color pattern, the result probability will be displayed andan optional audible alarm is given or not. Otherwise, an appropriatemessage is displayed on the LCD.

During the process of writing to the memory, (e.g., saving results orupdating database), the system is able to detect the memory capacity andgive the user a warning of full memory. In such a case, the user needsto clear the memory by deleting certain files before commanding thesystem to continue its work.

In one embodiment, the system executes a prime pump procedure to clearup air and chemical bubbles in the tubes of minimized length anddiameter once the system has been idled for more than 12 hours. If thesystem has not been used for the past 12 hours then the system promptsthe user to place an empty swipe sample into a clamp holder. Once aswipe sample is secured on the clamp holder, the system prompts user todo the prime pump procedure by pumping chemical solutions onto swipesample. During the prime pumps, the camera captures the image from theswipe and displays it on the LCD screen. During the prime pumps, no heatis applied to the swipe.

In one embodiment, in the main menu, user can see the date, the time andcurrent status of the system. The system can generate a warning alarmonce battery, chemical level and memory reach their minimal levels. Themenu also contains three (3) software programmable buttons, namely NewAnalysis, Previous Results, and Settings. User can interact with thesesoft buttons by using the five hard buttons. The New Analysis option ishighlighted as default. The usage of these soft buttons is as follows:

-   -   New Analysis: allows user to perform a new test.    -   Previous Results: allows user to trace back the data tested in        the past.    -   Settings: allows user to set parameters such as date, time, to        test the system reliability, or to connect to PC for firmware        and/or database update.

The user can see the images taken by the camera. The system status isalso displayed. In addition, three (3) soft buttons (Start, Stop, andStatus) are provided. The Start option is highlighted as default.

FIGS. 7A-7D (collectively FIG. 7) show an exemplary operational flowchart executed by the system of FIG. 1. When the system is turned on bypressing the Start Power On button, it will stay in IDLE state 304. Inthis state, the system waits for user commands. By default, both thecamera lighting LED and the fan are turned off. The system sends anappropriate message alarm to operator once chemical, battery, and memoryreach their minimal level. User may command the system to perform a newtest by selecting New Analysis, to view previous results and images byselecting Previous Results, or to update the firmware and/or database.

When the option of performing a new test is selected, the system checkswhether the Slide Door Switch closed or not (360). If the door is notclosed, it will display a warning message (400) and return to IDLE state304. Otherwise, it looks for a loaded Swiped Sample using the infraredsensor (362). The presence of the sample allows the system to move tothe next state, where it checks for the fluid levels of the threereservoirs to ensure that the fluids are enough for the entire testprocess (364). The amount of fluid is determined by the number ofdispersing (i.e., a full bottle is enough for a predetermined number ofdispersals and the number is decremented during each dispersing).

Before continuing, the system checks the temperature of the filament ifit is equal to 35° C. in one embodiment. Otherwise, it will have to heatthe filament until the temperature of the filament reaches 35° C. (374).At this temperature, the user is allowed to choose different options. Ifthe user presses the Stop button (368), the system will stop the workand return to the IDLE state. If the user chooses the Status button(370), the system will temporarily display its current task to turn thesystem status on/off. After that it returns and continues the previouswork. When the user presses Start button (372), the system turns the Fanon to blow the fog or vapor away from the camera, turns the LEDs on,turns the fan 39 to a low speed and takes a background image using thecamera (378). Then, the system will select a particular micro-pump N=1or a series of micro-pumps (N=1, 2, 3 . . . or a combination thereof)and start analyzing the sample based on the image analysis process(380-386). Once the New Analysis operation is in process, it takes anumber of different tests (in one embodiment seven tests) non-stop andsummarizes the test results after the last test has completed. The imageresults are saved automatically as a group by a time date stamp and canbe further sorted by positive or negative results for ease of viewingrecall (392-394). Different audible sounds can be played at the end ofeach test to catch the operators attention. The image result is obtainedby subtracting the current image from its initial background image.After finishing this analysis, the system asks user if he/she wants toreview the test summary or else return to the main menu.

When the option of viewing previous results is selected, the user canselect his/her desired filename and presses Display button to commandthe system to decompress and display the image and/or other necessaryinformation (402-408).

When the option of updating date, time, database and/or firmware isselected (306), the system shows a menu to allow the user to choosedifferent options such as update date, time, or upgrade the firmware, ortest the reliability of the system. For example, when the user pressesthe date button (308), the system allows the user to change the date viathe buttons of the system. After the date is confirmed to be changed,the system will store the change in its memory and return to theprevious menu to allow the user to choose other options. The change ofthe time functions in the same manner as the change of the date (310).

In case the user wants to update the database by pressing Databasebutton (316), the system communicates with the PC in order to set up achannel for data transfer (312). Upon a successful connection the usercan update database and/or firmware. After the firmware or database isupdated, the user presses the Ok button to return to the main menu. Whenthe system connects to the PC unsuccessfully, it warns the user to checkthe connection (316).

When the user wants to test the reliability of the system, the user canpress the Test button (322). As soon as this button is pressed, the usercan test different system parameters. He/she can save the changedparameter or restore default parameter. When the user presses Exitbutton, system returns to the main menu.

By having all components under program control and by arranging for aknown input to the system such as a controlled injection of targetmaterial, the system can perform self-calibration and self-diagnostic.The function of this program is to calibrate the entire system anddetermine and store the required time, and temperature parameter, amongothers. If these parameters are not within specified limits for anyreason, the program can alert the user. Guided by a service program theuser response can range from immediate shutdown to scheduling service ata later date, to simply noting the circumstances.

FIG. 8 shows an exemplary image analysis process executed by theprocessor 200 to detect chemical agents automatically. To start theanalysis process, the system turns the micro-pump(s) N (i.e., N=1, 2, 3. . . or a combination thereof) to disperse the chemical solution intothe Swiped Sample. The pumping rate is set to 2 Hz. After dispersingchemical solution, the system starts heating the sample to excite thechemical reactions. A current of about 1 Ampere is required to heat upthe filament. When the temperature of the sample reaches to a predefinedvalue, the system turns the heater off, the LED and the fan on. In oneembodiment, before commanding the CMOS image sensor to capture an image,the system waits for the chemical reaction under optimized: time,temperature, volume dispensed, and vapor to complete for around 1 ms.The captured image is then displayed on the LCD. The system creates aresult image by subtracting the captured image from the background one.Then the result image is compared with the color patterns in the lookuptable stored in the memory. If the results image matches some pattern,the result will be displayed and an audible alarm is given. Otherwise,an appropriate message is displayed on the LCD.

Due to the automated analysis, the system provides an objectiveindication of potential threats with more accurate results and moreconvenience.

The invention may be implemented in hardware, firmware or software, or acombination of the three. Preferably the invention is implemented in acomputer program executed on a programmable computer having a processor,a data storage system, volatile and non-volatile memory and/or storageelements, at least one input device and at least one output device.

By way of example, a block diagram of a computer to support the systemis discussed next. The computer preferably includes a processor, randomaccess memory (RAM), a program memory (preferably a writable read-onlymemory (ROM) such as a flash ROM) and an input/output (I/O) controllercoupled by a CPU bus. The computer may optionally include a hard drivecontroller which is coupled to a hard disk and CPU bus. Hard disk may beused for storing application programs, such as the present invention,and data. Alternatively, application programs may be stored in RAM orROM. I/O controller is coupled by means of an I/O bus to an I/Ointerface. I/O interface receives and transmits data in analog ordigital form over communication links such as a serial link, local areanetwork, wireless link, and parallel link. Optionally, a display, akeyboard and a pointing device (mouse) may also be connected to I/O bus.Alternatively, separate connections (separate buses) may be used for I/Ointerface, display, keyboard and pointing device. Programmableprocessing system may be preprogrammed or it may be programmed (andreprogrammed) by downloading a program from another source (e.g., afloppy disk, CD-ROM, or another computer).

Each computer program is tangibly stored in a machine-readable,removable storage media or device (e.g., program memory or magneticdisk) readable by a general or special purpose programmable computer,for configuring and controlling operation of a computer when the storagemedia or device is read by the computer to perform the proceduresdescribed herein. The inventive system may also be considered to beembodied in a computer-readable storage medium, configured with acomputer program, where the storage medium so configured causes acomputer to operate in a specific and predefined manner to perform thefunctions described herein.

The invention has been described herein in considerable detail in orderto comply with the patent Statutes and to provide those skilled in theart with the information needed to apply the novel principles and toconstruct and use such specialized components as are required. However,it is to be understood that the invention can be carried out byspecifically different equipment and devices, and that variousmodifications, both as to the equipment details and operatingprocedures, can be accomplished without departing from the scope of theinvention itself.

Although specific embodiments of the present invention have beenillustrated in the accompanying drawings and described in the foregoingdetailed description, it will be understood that the invention is notlimited to the particular embodiments described herein, but is capableof numerous rearrangements, modifications, and substitutions withoutdeparting from the scope of the invention. The following claims areintended to encompass all such modifications.

What is claimed is:
 1. A method to analyze a disposable test swipe,comprising: uniformly heating the disposable test swipe to apredetermined test area on the test swipe in a test chamber; exposingthe test swipe through predetermined timed temperature sequences;dispensing chemicals in timed sequences onto the predetermined test areathroughout a predetermined temperature profile and time sequence; andcapturing a sequence of colors evolving specific to each analyte on thetest area of the disposable swipe for differentiating, detecting, oridentifying specifically one of a plurality explosives by taking aseries of images, at specific heat and times in the sequence of chemicalreactions on the test area of the swipe for analysis.
 2. The method ofclaim 1, comprising performing an analysis of the reaction imagescollected throughout a test run in real-time.
 3. The method of claim 1,comprising controlling each pump to dispense one or more chemicalsolutions in a predetermined sequence.
 4. The method of claim 1,comprising heating the test area on the swipe to one or morepredetermined temperatures and hold times using an automatic rampedheating feedback control.
 5. The method of claim 1, comprising:providing a camera and an optics system with anti-fog protection;displaying a camera output in real-time; and storing and viewing imageswith a JPEG encoder and decoder.